1. Field of the Invention
The present invention relates to a chain having a plurality of inner links configured by coupling a pair of front and rear bushings to a pair of left and right inner plates, and a plurality of outer links configured by coupling a pair of front and rear connecting pins to a pair of left and right outer plates, the inner links and outer links being alternately and pivotably coupled together in the longitudinal direction of the chain by inserting the connecting pins into the bushings.
2. Description of the Related Art
A chain 110 has been known, as shown in FIG. 4, which includes a plurality of inner links 120 configured by coupling a pair of front and rear bushings 140 to a pair of left and right inner plates 130, and a plurality of outer links 150 configured by coupling a pair of front and rear connecting pins 170 to a pair of left and right outer plates 160, the inner links 120 and outer links 150 being alternately and pivotably coupled together in the longitudinal direction of the chain by inserting the connecting pins 170 into the bushings 140 (see, for example, Japanese Patent Application Laid-open No. 2005-021911).
Such a chain 110 was conventionally encased in a packing box when delivered as a product or at some such time, such that the entire chain 110 is bent in a U-shape in which the outer links 150 on both sides of one inner link 120 pivot relative to the inner link 120 as shown in FIG. 5A, or the inner links 120 on both sides of one outer link 150 pivot relative to the outer link 150 as shown in FIG. 5B.
If the links 120 or 150 on both sides of the link 150 or 120 that serves as a pivot base open in a V shape at this time, the chain cannot be encased in a compact manner. For this reason, the plate height H1 of the inner plates 130 and the plate height H2 of the outer plates 160 were set not greater than the chain pitch P. FIG. 5A and FIG. 5B show an example in which the plate height H1 of the inner plates 130 and the plate height H2 of the outer plates 160 are set the same as the chain pitch P.